In contrast to repeated past failures to obtain human-human hybridomas secreting human immunoglobulin in our laboratory, we now have developed the methodology to isolate large numbers of such hybrids secreting human immunoglobulin. This method offers advantages over previous serological approaches to study tumor immunity. With this background, we plan to further develop the human monoclonal antibody methodology, including conditions for human-human hybridoma and subsequent immunoglobulin secretion and establishment of new human myeloma cell lines. In addition, we will study local and regional tumor immunity, with lymphocytes from tumor infiltrates and regional lymph nodes to generate human monoclonal antibodies. Human monoclonal antibodies will be produced using peripheral blood lymphocytes from melanoma patients who are being vaccinated with autologous and allogeneic melanoma cell preparations and from cancer patients and healthy individuals who have antibodies in their serum to unique and shared human cancer antigens. The way is now open to a broad analysis of specificity of human monoclonal antibodies to human cancer antigens.